When I was young I wanted to be a jet fighter pilot. Only after I discovered that I was color blind and ineligible to get anywhere near a cockpit did I consider my second passion of photography, black-and-white photography (which I began at age eight).

How did you get started in your field of work?

I started as a photographer, writer, and editor for both my high school yearbook and newspaper. At the same time I lived in Bishop, California, a spectacular town right below the dramatic eastern escarpment of the Sierra Nevada. Mountains rose 10,000 vertical feet to either side of our valley and it was only natural that I would be drawn to them. I had been camping and adventuring with my parents since before I could walk and by age 16 started relatively serious rock climbing and mountaineering, both in the adjacent Sierra and nearby Yosemite National Park.

While still in high school I met an up-and-coming climbing photographer named Galen Rowell who befriended me and coached me about the profession. Within a year or two he shot a cover story for National Geographic magazine and I realized that even "real" people could do those kinds of things (although it would take me much longer than Galen).

After two years of college I began traveling as a vagabond, first in Europe and then as a student in Nepal. During this period another friend helped me get my first pictures published in an early outdoor magazine called Mountain Gazette. Later, when activities such as climbing, hiking, backcountry skiing, and trekking became more popular and magazines such as Outside and Backpacker appeared, they turned to Mountain Gazette for many of their contributors, including both Galen and me.

What inspires you to dedicate your life to photography?

I actually photograph many subjects, each for different reasons. I am best known for my expedition and adventure photography, which was a logical consequence of growing up under the spell of some of America's most beautiful peaks. Equally important to me, however, are the people who live in remote places, such as Nepalis, Mongolians, the Inuit, Peruvians, Uygars, Bedouins, and the like. This passion for the diversity of human cultures began with my living for three months with a Nepali family that did not speak English (forcing me to learn Nepali) and has only grown with every place I visit. Looking back, some of my favorite stories for National Geographic magazinewere only about people, not expeditions. Notably, after evading my college language requirement because "it had no relevance to my future," I now taught myself varying proficiency in at least six different languages.

What's a normal day like for you?

No two days are the same for me. Unlike many people's perceptions, however, I spend most of my time in my office, sitting in front of a computer doing a host of things from writing to photo editing to creating proposals and planning expeditions. The best part, though, is in the field. Even there, however, every trip is different. Some expeditions find me hanging off overhanging polar cliffs, wondering if I'll survive to the end of the day, while others have found me mushing behind dogsleds across the frozen Arctic Ocean, hunting in the Amazon cloud forest for undiscovered Inca mummies, or galloping across the Mongolian steppes, hoping not to fall off my horse while still trying to shoot pictures one-handed.

Do you have a hero and, if so, why is this person your hero?

My heroes are more a category of people than any particular individual. Almost all of them are notable photographers, mountaineers, and explorers who have showed the world just a bit more than it had seen before. Although I hesitate to list them, some obvious examples are Ernest Shackleton and Douglas Mawson of Antarctic fame, photographer Ansel Adams, conservationist John Muir, Sierra mountaineering pioneer Norman Clyde, and a host of people who are still alive.

What's been your favorite experience in the field? Most challenging?

This is an unfair question, because every experience is rich in different ways, even some of the miserable ones. I have also been blessed to have experienced far more than my fair share of experiences.

Just to take a stab at it, however, I think that my favorite experience was a big-wall mountaineering expedition that I led and photographed in Queen Maud Land, Antarctica, an almost surreal landscape that had scarcely been explored. We had an incredible group of six people, each incredibly talented in their own unique ways, and as a team we accomplished what is arguably the first ever big-wall climb in Antarctica—up an overhanging 2,000-foot granite fin called the Razor.

My most challenging experience was probably on my first National Geographic assignment to photograph an expedition exploring the Cordillera Sarmiento, a little-known range at the extreme southern tip of Patagonian Chile. There proved to be good reason that there was no record of any mountaineering or other inland exploration there. Rising above the Chilean fjords, these mountains catch the full blast of nearly nonstop storms howling out of the Pacific Ocean's notorious "Furious Fifties."In two months we had only five or six good days, and at times were trapped by 130-plus-mph winds in snow caves where all of our clothes and sleeping bags were soaked, and we ran out of food and barely made it back to base camp. Nevertheless, that proved to be what it took to create some of the best photography of my life to date (including not just pictures of our misery, but also some magnificent scenes of us standing atop mountains surrounded by views no one had ever seen before).

What are your other passions?

I have always enjoyed long canoe trips, adventures with my family, ambitious home remodeling, and other outdoor sports such as alpine skiing, backcountry skiing, mountain biking, and whitewater kayaking. I am also quite passionate about wilderness preservation and do what I can to educate people about how important such places have always been not just to our human spirit, but also to our survival as a species. I am also especially fond of public speaking on a variety of topics.

What do you do in your free time?

Beyond what I have described above—which in itself often feels like free time—I love to read well-written books about a variety of topics and to watch creative movies and innovative television. As much as it often makes me angry, too, I love to stay abreast of world news.

If you could have people do one thing to help preserve the world as a more viable place, what would it be?

If I could have people do one thing to help preserve the world as a more viable place it would be to learn how to tread more lightly on our planet, both physically and metaphorically. Earth simply does not have the resources to support everyone at the standards of living that the richest people enjoy today (including most Europeans and Americans). If we are to avoid bloodshed and possible destruction of life as we know it, everyone is going to have to learn how to compromise and find happiness with things other than mere material "success."